diff options
Diffstat (limited to 'drivers/tty/mxser.c')
| -rw-r--r-- | drivers/tty/mxser.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c index 1c0c9553bc05..7dd38047ba23 100644 --- a/drivers/tty/mxser.c +++ b/drivers/tty/mxser.c @@ -246,11 +246,11 @@ struct mxser_port { unsigned char err_shadow; struct async_icount icount; /* kernel counters for 4 input interrupts */ - int timeout; + unsigned int timeout; int read_status_mask; int ignore_status_mask; - int xmit_fifo_size; + unsigned int xmit_fifo_size; int xmit_head; int xmit_tail; int xmit_cnt; @@ -572,8 +572,9 @@ static void mxser_dtr_rts(struct tty_port *port, int on) static int mxser_set_baud(struct tty_struct *tty, long newspd) { struct mxser_port *info = tty->driver_data; - int quot = 0, baud; + unsigned int quot = 0, baud; unsigned char cval; + u64 timeout; if (!info->ioaddr) return -1; @@ -594,8 +595,13 @@ static int mxser_set_baud(struct tty_struct *tty, long newspd) quot = 0; } - info->timeout = ((info->xmit_fifo_size * HZ * 10 * quot) / info->baud_base); - info->timeout += HZ / 50; /* Add .02 seconds of slop */ + /* + * worst case (128 * 1000 * 10 * 18432) needs 35 bits, so divide in the + * u64 domain + */ + timeout = (u64)info->xmit_fifo_size * HZ * 10 * quot; + do_div(timeout, info->baud_base); + info->timeout = timeout + HZ / 50; /* Add .02 seconds of slop */ if (quot) { info->MCR |= UART_MCR_DTR; |